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    <title>ShellCheck: SC1142 – Use `done < <(cmd)` to redirect from process substitution (currently missing one `<`).</title>
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    <h1>SC1142 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC1142">See this page on GitHub</a>
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    <h2
id="use-done--cmd-to-redirect-from-process-substitution-currently-missing-one-">Use
<code>done &lt; &lt;(cmd)</code> to redirect from process substitution
(currently missing one <code>&lt;</code>).</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC1142.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="va">sum</span><span class="op">=</span>0</span>
<span id="cb1-2"><a href="SC1142.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="cf">while</span> <span class="va">IFS</span><span class="op">=</span><span class="st">&quot;&quot;</span> <span class="bu">read</span> <span class="at">-r</span> <span class="va">n</span></span>
<span id="cb1-3"><a href="SC1142.html#cb1-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
<span id="cb1-4"><a href="SC1142.html#cb1-4" aria-hidden="true" tabindex="-1"></a>  <span class="kw">((</span> <span class="va">sum</span> <span class="op">+=</span> <span class="va">n</span> <span class="kw">))</span></span>
<span id="cb1-5"><a href="SC1142.html#cb1-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span> <span class="op">&lt;(</span><span class="fu">file</span><span class="op">)</span> </span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC1142.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="va">sum</span><span class="op">=</span>0</span>
<span id="cb2-2"><a href="SC1142.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">while</span> <span class="va">IFS</span><span class="op">=</span><span class="st">&quot;&quot;</span> <span class="bu">read</span> <span class="at">-r</span> <span class="va">n</span></span>
<span id="cb2-3"><a href="SC1142.html#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="cf">do</span></span>
<span id="cb2-4"><a href="SC1142.html#cb2-4" aria-hidden="true" tabindex="-1"></a>  <span class="kw">((</span> <span class="va">sum</span> <span class="op">+=</span> <span class="va">n</span> <span class="kw">))</span></span>
<span id="cb2-5"><a href="SC1142.html#cb2-5" aria-hidden="true" tabindex="-1"></a><span class="cf">done</span> <span class="op">&lt;</span> <span class="op">&lt;(</span><span class="fu">file</span><span class="op">)</span> </span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>ShellCheck found a <code>done</code> keyword followed by a process
substitution, e.g. <code>done &lt;(cmd)</code>.</p>
<p>The intention was most likely to redirect from this process
substitution, in which case you will need one extra <code>&lt;</code>:
<code>done &lt; &lt;(cmd)</code>.</p>
<p>This is because <code>&lt;(cmd)</code> expands to a filename (e.g.
<code>/dev/fd/63</code>), and you need a <code>&lt;</code> to redirect
from filenames.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None</p>
<h3 id="related-resources">Related resources:</h3>
<ul>
<li>Help by adding links to BashFAQ, StackOverflow, man pages, POSIX,
etc!</li>
</ul>
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